1. Field of the Invention
This invention relates to anatomic cardiac imaging and electro-anatomical mapping. More particularly, this invention relates to synchronized display of 3-dimensional ultrasound images and electro-anatomical maps of the heart.
1. Description of the Related Art
The meanings of acronyms and certain terminology used herein are given in Table 1.
TABLE 1CTComputed Tomography; Computed TomographicECGElectrocardiogramHIFUHigh Intensity Focused UltrasoundIODInformation Object DefinitionMRIMagnetic Resonance ImagingPETPositron Emission Tomography
Methods for three-dimensional geometrical mapping and reconstruction of the endocardial surface are known in the art. For example, U.S. Pat. No. 5,738,096, whose disclosure is incorporated herein by reference, describes methods for mapping the endocardium based on bringing a probe into contact with multiple locations on a wall of the heart, and determining position coordinates of the probe at each of the locations. The position coordinates are combined to form a map of at least a portion of the heart. These methods are effective and accurate, but they require substantial time and skill to carry out.
Hybrid catheters are now known that perform ultrasound imaging in conjunction with position sensing. Such devices are disclosed, for example, in commonly assigned U.S. Pat. Nos. 6,690,963, 6,716,166 and 6,773,402, which are herein incorporated by reference. Medical applications include 3-dimensional mapping of a cavity of the body, as well as measurement of chamber wall thickness and wall velocity and mapping of electrical activity. In medical applications, it is common to acquire maps and images of body organs by different modalities, which are to be interpreted in relationship to one another. An example is correlation of an electro-anatomical map of the heart and an image, such as a 3-dimensional ultrasound image.
Commercial electrophysiological and physical mapping systems based on detecting the position of a probe inside the body are presently available. Among them, the Carto-Biosense® Navigation System, available from Biosense Webster Inc., 3333 Diamond Canyon Road Diamond Bar, Calif. 91765, is a system for automatic association and mapping of local electrical activity with catheter location.